March 5th is the official “Learning from Lei Feng Day” when people are to learn from Lei F

问题补充：

March 5th is the official “Learning from Lei Feng Day” when people are to learn from Lei Feng, a cultural image symbolizing selflessness and contribution.

A. called on

B. called up

C. called in

D. called off

答案：

(答案→)A. called on

B. called up

C. called in

D. called off

解析：call on号召；call up 打电话； call in 下令收回；call off 取消；句意：三月五日是号召人们学习雷锋的官方“学雷锋日”，雷锋是一个象征着无私和奉献的文化形象。